Pneumatic action.



F. A. LANDGREN.

PNEUMATIC ACTION. APPLICATION FILED JUNE 28,1913.

Patented D60. 5, 1916 2 .SHEETS-$HEET 1.

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F. A. LANDGREN.

PNEUMATIC ACTION; APPLICATION'FILED JUNE 23. I9l3.

m Dec. 5,1916.

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UNITED STATES PATENT OFFICE.

FREDERICK A. LANDGREN, OF SYCAMORE, ILLIN PNEUMATIC ACTION.

Application filed June 28, 1913.

To all whom it may concern Be it known that I, Fiinonnion A. LAND- GRI'JN, a subject of Sweden, residing at Sycamore, in the countyof Dekalb and State of Illinois, have invented new and useful Improvements in Pneumatic Actions, of which the following is a specification.

The invention relates to a pneumatic action for player pianos, and more particularly to the class of unit attachments for automatic player pianos.

The primaryobject of the invention is the provision of an attachment wherein the series of units can be separately connected to a vacuum chamber-so that any one of the said units can be removed for repairs and replaced without disturl'iing the remaining units or the player action.

Another object of the invention is the provision of an attachment wherein the units canEbe positioned in" close relation to each other .'without interference and to assure compactness to avoid utilizing excessive space bythe neumatics in the player action: Ar further object of the invention is the provision of an atti'ichinent which enables free accessibility to the units of the pneu- "niaticso that when it is desired to remove any one ofithe units the pl'ayer'action will not haveto be removed from the piano, and any one of the said units can be detached without removal or detachment of all or any of the other units.

A still further object of the invention is the provision an attachment of this character wherein units can be properly distributed so that each note will be controlled by a distinct element or train of-operative parts, each of which is singly detachable and may be removed without disturbing the other operativeelements for the remaining notes or vwithout necessitating the removal of the player action from the instrument. the units being accurate and quick in action "to assure the perfect working, of the player piano.

I A still further object of the invention is the provision of an attachment of this character which is simple in construction and inexpensive in manufacture.

\Vith these and other objects in view, the

invention consists in the constructionQcombination and arrangement of parts as will be hereinafter fully described, illustrated in the accompanying drawing, and pointed out in the claim hereunto appended.

In the drawings Figure 1 is a front ele- Specification of Letters Patent.

Patented Dec. 5, 1916.

Serial No. 776,343.

vention thereon. Fig. 2 is a sectional view on the line 2 2 of Fig. 1. Fig. 3 is a horizontal sectional View through the pneumatic and vacuum chambers. Fig. i is a fragmentary sectional view on the lines-4 of Fig. Fig. 5 is a vertical transverse sectional view through one of the units.

Similar reference characters indicate corresponding parts throughout the several views in the drawings;

Referring to the drawings by numerals, the units each comprise a main supporting block 5 and the valve block 6 mounted on the main block and removably secured thereto as by means of screws 7. Hinged at the left lower edge of the block 5 is the movable member or plate 8 having at its right end an extension or shelf 9 for engaging directly or through connecting mechanism with'the abstract rods or striking mechanism of the piano. Glued or otherwise secured about the edges of the block 5 and plate 8 is flexible fabric 10 whichwith said block. and-plate forms a bellows chamber 11. The block 5 is recessed from the top to form a lowerdiaphragm chamber 12 over which hangs a diaphragm 13. Into' the valve block 6 is cut the upper diaphragm chamber 1-4 which is separated from the lower chamber 12 by the said diaphragm -13, ant hinged at the left end of the said upper chamber 14: and extending diametrically across the same and over the diaphragm is a. lever 15 carrying near its free end a resilient disk 16 which rests upon a pad 17 superimposed upon and fixed to the dia- .phragm 13 so that when the diaphragm is mosphere. The wall 19 separating the said chamber 18 from the chamber 1 1 is provided with an opening 2-2 connecting the valve chamber with the upper diaphragm chamber, which is closed in a manner presently described. 1

lVithin the valve chamber 18 is a circuvertical uprights 29 connected thereto,

.lar-slrapcd or disk-like valve 23 which is fixed to a valve stem or lug 24', the same be ing fixed to the lever 15 so that on the raising of the said lever the valve 23 will close the opening 521 and on the lowering of the said lever the valve will close the opening 22, thereby alternately permitting co'nr munication from the atmosphere with the valve chamber and also communication between the valve chamber andthc upper diaphragm chamber.

The left ends of the blocks 5 and .6 are in vertical register and are secured together 'by' means of the screws 7 which engage the said block 5 and are passed through the valve block 6, while the valve block 6 is secured to one wall of a'vacuum chamber frame presently described.

Formed in the valve block 6 at the left end thereof are vertical passages 25, the same opening into leads or vents 26 communicating with the. that when the valve 28 closes the port 21 communication is had between the vacuum chamber 80 and the bellows 11 through the opening 22 while formed in the right end of the valve block 6 is'an opening or port 27 which leads to the upper diaphragm chamber 14: and is adapted to communicate with oneof the channels in the vacuum chamber frame presently described.

The vacuum chamber frame comprises a series of horizontallyarranged bars 28 ailid tie bars beinghollow to form vacuum channels 30, while one of the uprights is made hollow to form a vacuum channel 31 communieating with the said channels 30, and this mounted thereon nuts port37 in the channel 31 is suitably connected with the main suction'be'llows or device of any approved construction of the player action. The valve block 6 of each unit is formed in its opposite longitudinal side edges with rooves 32 receiving suspension or holding rods 3,3, the inner threaded ends 34; of which are. engaged inone wall of the vacuum chamber frame, v ends 35 of said rods have adjustably 36 which work against the left or front end of the valve block 6' and in this manner the unit issecured to the vacuum chamber frame,.which is clearly shown in Figs. 1 and 2 of; the drawing. The port 27 in the valve block Gregisters with a wall of one'of the bars 28 so that communication between the upper diaphragm chamber i l will be had with the channel 30 in the said bar. A. passageway 38 connects the lower diaphragm chamber 1 2 with a tube 39 which has connection with and leadsto an opening in the trackerboard over' which the music sheet travels,

valve chamber 18, so

while the outer threaded :of longitudinal the tracker board not being shown. When the tracker board openings are closed the upper diaphragm chamber 'll communicates with the vacuum channel 30; the diaphragm is down and the valve is held against its seat for closing the opening 22. When a tracker board opening is exposed by the sheet air under atmospheric pressure rushes through the tube 39 and passage 38 to blow up the diaphragm and to raise the valve. The valve now closes atmospheric outlet 21 and allows the bellows compartment or chamber 11 to connect with the vacuum chamber 30 through the passages 25 and openin 22. The movable plate 8 is thereforeraise and the piano striking mechanism having connection with the shelf 9 is actuated. hen the tracker board opening is again closed the pressure in the, diaphragm chambers equalizes and the valve returns to lowered position to disconnect the bellows chamber from the vacuum chamber or channel 30 and the class described;v in combination, a suction chamber, a channel. unit consisting of a main support block and a valve block mounted at one end upon-said main blockpsaid valve block adapted toengage one side of said suction chamber flush with its top and bottom and said main supporting block projecting in advance of said valve block and secured to the bottom of said suction chamber, a top plate secured upon said valve block and having a} portion overlapping the upper part of said suction chamber, said valve block and suction chamher being formed with registerable ports,.,

said valve block being provlded with a pair side grooves,'a pair of 'susthreaded into said suction pension rods chamber snugly embedded-in said grooves. and having threaded portions projecting beyond the valve block, and nuts engaging; the threaded ends of said ports'an'd clamp;

ing said .valve block against said suction chamber.

In testimony whereof I affix my signature in presence of two witnesses,

FREDERICK A. LANDGREN. Witnesses:

WM. J. FULTON, JOHN FAISSLER. 

